I'll translate: he's saying you should give more information about your problem if you want us to help you. Saying something as vague as "i get an error message" is just as vague as "my car is broken please help", exception being that we have no physical way to judge your problem.

Here's a list of helpful informations that probably should have been in your original post if you wanted to fix your problem better

SD card is probably too big. Devmenu crashes if it has to display a bigger free space size than it can. Shrink the partition on your SD card and try again. (you wont lose anything)
Had this problem myself.